The invention relates generally to a system for processing mail items, in particular to an apparatus for arranging flat such items into a specifiable sequence of delivery points assigned to recipient addresses.
Mail sorting offices process millions of mail items a day in preparation for their delivery to individual recipient addresses. The term “mail item” encompasses letters, magazines, and periodicals, as well as mailed books and other flat such items. Before, for example, a mail-delivery operative starts making deliveries, a mail-processing system sorts the mail items in a mail sorting office. One of said operative's tasks is to arrange the mail items in the order in which they will be delivered so as to achieve efficient delivering.
A mail-processing system is highly automated in order to manage the number of items mailed daily. The mail-processing system can contain a system that processes the mail items, packages them according to delivery points, then arranges the resulting volumes into their delivery sequence (it is also called a DPP system, where DPP stands for Delivery Point Packaging). Alongside further functions, processing includes singling the mail items, reading their recipient addresses, grouping them, and carrier-sequencing them according to their recipient addresses. While generally expected to operate efficiently and reliably, mail-processing systems of said type should at the same time avoid subjecting the mail items to excessive handling so that said items will sustain no or only minor damage.
For arranging mail items into a specific sequence a solution was known (EP 820 81 8 A1) that employs a temporary storage device consisting of pouches or similar elements each able to accept one mail item and feed it out again into the actual receptacle compartment in response to a control instruction. All mail items requiring to be thus arranged are therein first placed into the temporary storage device's pouches in any order. Said items are then removed from the temporary storage device's pouches and transferred to the receptacle compartments in such a way as to be located in the latter in the order requiring to be established. A separate receptacle compartment is provided for each mail item. Sorting takes place over two circulations of the temporary storage device's pouches: One circulation for filling and another for emptying the pouches.
That, however, requires a large number of receptacle compartments each having to be fitted with a control mechanism that initiates transfer of the mail item from the correct pouch of the temporary storage device.
Known also was a corresponding solution wherein in each case a plurality of mail items are stacked in ordered fashion into the receptacle compartments. The mail items are transferred from the containers to the receptacle compartments over a plurality of circulations, with the sequence of the mail items in each receptacle compartment corresponding to the sequence of the delivery points assigned to the addresses of the mail items located in the respective receptacle compartment (DE 199 43 362 A1).
Known from U.S. Pat. No. 3,573,748 is an apparatus wherein mail items are emptied from static pouches onto a segmented output conveyor, and known from U.S. Pat. No. 5,462,268 A is an apparatus wherein mail items are emptied into containers from circulating pouches and hence into sections of a conveyor.
Known from WO 2005/025763 A1 is a process description for carrier-sequencing by means of a sorting system having a temporary storage device. Mailing volumes that can be larger than the temporary storage device's storage capacity are therein processed efficiently.